Furnace door



Patented lAug. 17, 1943 ,Y UNITED STATES PATENT OFFICEV FURNACE DOR Charles H. Russell, McKeesport, Pa.

Application January 23, 1941, Serial No. 375,692

2 Claims.

This invention relates to imrovements in furnace doors of the character adapted for heating furnaces, as for example, open hearth furnaces and the like.

In prior practice, such furnace doors have generally been of solid rigid construction suspended over the furnace opening in the usual manner. Such doors have beenv found to be too inflexible and to warp under the heat of the furnace, causing either the ends or the center portion of the door to be disposed or pull away from the furnace. Thus, cold air gains access to the furnace, making it difficult to maintain uniform temperatures and increasing fuel con sumption.

I have discovered that these diiculties may be obviated in an economical and simple manner by constructing the door so as to permit the same to expand and contract with the furnace wall.

My invention contemplates the provision of an articulated door so disposed and constructed as to insure the close conformity thereof with the furnace wall under expansion due to heat.

Additional objects and advantages of the in vention will become apparent from the following description, taken in connection with the accompanying drawing, wherein:

Fig. 1 is an elevational view of a furnace embodying my invention;

Fig. 2 is a top plan View thereof;

Fig. 3 is an end elevation thereof;

Fig. l is a cross-section taken on the line V--IV of Fig. 1; and

Fig. 5 is an elevational View of a rnc-dined form of door, embodying rthe invention.

Referring to the drawing, the improved furnace door is shown'positioned over the opening of a furnace'A, as for example, an open hearth furnace, said door comprising at least two vertically disposed parts 2 and'S hinged at their meeting vertical edges, as indicated at i-L The parts Vor sections 2 and 3 are preferably formed of cuter metal plates or shells 5 filled or lined with refractory7 6, as shown in Fig. 4 said refractory lining being v'disposed toward the interior of the furnace A.

door

The hinged sections 2 and 3 thus provide an ears 9 are preferably secured to the door sections substantially in the vertical planes of their respective centers of gravity, whereby the hinged assembly is in substantial balance when suspended vertically over the furnace opening. The bottom edge of the door may engage the foreplate H3 of the furnace when the door is in closed position.

The hinged connections 4 4 preferably have sucient play therein to permit the center portions of the door sections 2 and 3 to move inwardly and outwardly in response to a corresponding movement of the furnace wall. Such furnaces generally bow or belly horizontally outward at their door sections when heated, and the articulated door of my invention may deflect therewith Vwithout destroying the closing function thereof. It will be observed that any tendency to produce such outward displacement of the center of the door will result in a conforming pressure of the door upon the furnace wall, thus maintaining a proper closure, said pressure resulting from the corresponding outward displacement of the lower ends of the bridle -l, the upper end of said bridle (not shown) being maintained over a pulley or the like, as is customary.

Where spaced hinges 4 4 are employed as in Fig. 1, I prefer to seal the vertical meeting edges of the door sections 2 and 3 between said hinges by a cover plate or stops! I, said plate being carried by one door section and overlying the face of the other door section.

Fig. 5 illustrates a modified form wherein the door sections 2 and 3 are joined by a single vertical hinge ll extending substantially throughout the vertical height of the center portion of the assembled door.

It will be apparent that a furnace door of the character described will possess sufficient ilexibility, due to its plurality of self-adjusting sections, to readily and simply conform to the furnace wall and maintain a suitable closure in service. By reducing the dimensions of the door sections or parts, the tendency thereof to warp is likewise minimized, thus providing a highly economical and ecient door. Such a door will have a long life of service.

Various Vchanges and modifications are contemplated within vthe scope of the following claims.

I claim:

l. An articulated door adapted to be freely and vertically suspended over a vertical furnace opening or the like, said door including a pair of vertical sections having their adjacent vertical edges hinged to permit relative movement of said sections in a horizontal direction, means for suspending said sectons in substantial balance including a hanger attachment disposed in the Vertical plane of the center of gravity of each section, common suspending means connecting said attachments, whereby said door may conform to the face of the furnace Wall about the opening in accordance with the deformation of said wall face due to heat, and means at the hinge connecticn of said sectonscoverng the joint between the sections during relative movement thereof.

2. An articulated door adapted to be freely'and vertically suspended over a vertical furnace open .ing or the like, said door including a pair of vertical sections, spaced hinges connecting the sections at their adjacent vertical edges, a bridle having attachment with the upper edge of each section substantially in the vertical plane cf its center of vgravity for freely suspending the door, whereby said door may conform to the face of the furnace wall about the opening in accordance With the deformationV of said Wall face due to heat, and a cover plate secured to one section and overlying the other section at their adjacent vertical edges, said plate'extending between the hinges, whereby the joint` between the sections is covered during relative movement thereof upon said hinges.

CHARLES H. RUSSELL. 

